Connector repeater-switch of automatic telephone-exchanges for handling fire-alarm calls.



l. ERICKSON.

CONNECTOR REPEATER SWITCH 0F AUTOMATIC TELEPHONE EXCHANGES FOR HANDLINGFIRE ALARM CALLS.

APPLICATION FILED FEB. 25. 1914. RENEWED APR. 24. 1916.

1,228,007. Patented May 29, 1917.

svunntoz l Jbhn Erickson/ a UNITED STATESZ PATENT OFFIC -.1

JOHN nnrcxsou, or cmcaco, rnrnvorsfassrenon, BY mnsm: sssremmnrs, "ronocnns'rna n. access, or nocnnsrna,,,new roam CONNECTOR HEATER-SWITCH OIAUTOMATIC TELEPHONE-EXCHANGES FOB Specification of Letters Patent.

HANDLING FIRE-ALARM CALLS.

Application filed February 25, 1914,'Seria'1No. 821,097. Renewed April24, 1am. Serial-Ho. eases.

To all whom it may concern: r

Be it known that I, JOHN 'EmoKsoN, of Chicago, in the county of Cook andState of Illinois, have invented certain new and useful Improvements inthe Connector Reeater Switches of Automatic Telephonexchanges forHandling Fire-Alarm Calls; and I do hereby declare the following to be afull, clear, and exact description of the same, reference being had to.the accompanying drawings, forming a part of this'specification, and tothe reference-numerals marked thereon.

My present invention has for its object to provide certainimprovementsin the ar rangement, adjustment and means of operating-the connectorrepeater switch ofan v automatic telephone exchange system whichisvu'sed for the transmission of the impulses of current employed foractuating therfire alarm signal-recording mechanism at. the firedepartment headquarters after theconnection with said circuit has beenestablished throughthe various selector switches which are em 'loyed forconnecting through the central '0 cc or exchange the subscribers circuiton'which the call ,is initiated. To

these and other ends the invention consists I -in certain improvementsand combinations of parts, all as will be hereinafter more fullydescribed, the novel .features being pointed out in the claims at theend of the specification.

showing'a' subscribers line circuit equipped- In the drawings: Thefigure .is a diagrammatic illustration with a signal mechanism andindicating said circuit extended through'the first, sec- The inventionwill best be understood by 0nd and third selector switchesto the.repeater switch embodying thepresent invention asused in practice m-alarge exchange.

' Similar reference numerals throughout a brief description of thedifliculties encount'ered in attempting to operate fire alarm I signalsover an automatic telephone exchange system in which the subscriberssetup their desired connectionsby means of an impulse 'transmittinmechanism comprising a-dial A which t e operator. adjusts by impartingthereto a partial revolution and whi h, when released, will transmit oneor 'more impulses which control the operamoved a shorter distance itwill despatch nine, eight, etc. impulses or only one 1mpulse. In anautomatictelephone exchange of one thousand lines or under the connec-Patented May'29, 1917.

tions between any two subscribers circuits will be effected by the useof one selector and one connector switch, and in larger exchanges thenumber of selectors is increased,

although the operation of the additional switche'slis the same,.the callbei received in the first selector, transmitted it to a second selector,thence to the thir selector and eventually to the connector. A detai eddescription and construction of these switches and their operation isnot required because of the general knowled of these mechanismspossessed by those skilled in the telephone art, although iorconvenience as a means oi reference on this subject would mention thepatents granted {jointly to mg Alexander.

J self, Charles J. Erickson an Keith for automatic telephone connectorand selector switches, Nos. 815,176 and 815,321, respectively, issuedMarch 13, 1906,

which disclose generally the arrangement of;

the 'banks of contacts, and the rotary and vertically movable. shaftscarrying the I wipers cooperating'with said contacts, a1 though it willbe understood, of course, that the electromagnetic operatin devices bywhich these movements are e ected may be changed to suit variousconditions of service. v I

These central ofiice automatic switches when actuated to connectasubscribers'cin cuit with the fire alarm circuit leading'to firedepartment headquarters are not controlled in their/movements bythe dialAbutby "the alarm signal boxmechanism, and.

the purpose of my invention, as will hereinafter appear with greaterparticularity, is

ito' so arrange the alarm box'mechanism and the switching apparatusthat, in the event a subscriber erroneously endeavors mama lishconnection with the fire department headquarters by the o eration of thedial A," either by accidenta y oallingrthe wrong number or by afpremeditated'attempt to establish such a nne ti mthe s t hes ovaconnected through to the connector repeater switch.

The primary difliculty which has been encountered heretofore is due to.the fact thattelephone subscribers or operators in establishingconnections through the various switches would, through error in theoperation ofthe dial A cause the switches at the central oflice to setup a connection with the fire alarm circuit with the result that uponthe subsequent rotation of the dial. in an attempt to complete thenumber of the station-they intended to 'call would cause the actuationof the signal gong and'regist'er of the fire department headquarters.For instance, if the last digit of the number called was 5 a correspondistrokes would be imparted to t e gong and giving what would otherwise betermed a false alarm.

1 These difiiculties I have been able to eliminate by connecting thefire alarm circuit to the last set of contacts in the row of contacts onthe" connector switch; making all the other contacts busy, and somountingthe wipers on the connector shaft that in order to reach thefire alarm circuitcontacts it is necessary that the rotary movementimparted to said shaft shall be at least one step more than isordinarily required, i. e. if the connector switch is provided with tensets of contacts in a row, then 'I would adjust the wipers so thateleven or required to be imparted to the rotary shaft to bringsaidwipers into engagement with the last set of contacts. Therefore, tensteps oranything less than this number of move-. ments caused by theoperation of the dial A would effect the release of the connectorrepeater switch automatically in the usual manner by which said releaseis effected, but as the signaling box B is capable of transmittingeleven or more "impulses it is- PCS-w sible, therefore, to arrange theapparatus so that the wipers of-the' connector switch can' only be movedinto engagement with the last set of contacts by the movement of saidbox mechanism.

As a type of signal box mechanism which may in part begutilized foractuating the automatic switches, reference is made to Patent No.958,719, issued May 24 1910, to F. S. Bronson, for signal box for firealarm sys-. tem, and to my pending alplication, Renewal Serial No.793,470, filed, October 4,

1913. This mechanism comprises an arbor B carrying a switch actuatingwheel G and a code wheel D, the former being provided with the necessarygrooves or notches whereby circuit contacts are opened .and closedselector switches re eater switch, is prov ded wit other'nsets of tosuccessively actuate the and finally the connector. and the latternumber of a circuit composed of wires r,

more steps would be' notches which control the transmission ofimpulsesover the circuit previously established to transmit to the firealarm headquarters the code signal of this particular alarm despatchingmechanism. In the fi her of steps of the Wipers of the connectorrepeater switches to complete the'connection of the subscribers circuitwith the fire alarm circuit, after which the code signal is despatchedby impulses sent over the line y opening and closing the contactscontrolled by the wheel D.

In order to illustrate my invention in "detail I have shown theconnector switch mech-v anism in its simplest form, many of the partsrequired in' actual service being omitted. The rotary shaft, as thethree wipers s s and s which cooperate with the three rows of horizontalcon-' tacts. The rotary movement of the shaftis caused by therotarymagnet R arranged in r, over which the rotary impulses are imparted bythe eleven notches or recesses c on the wheel C. The trunk or circuitleading to the fire alarm headquarters comprises the wire i connected tothe last terminal in the upper row which is engaged by the wiper s whenthe latter takes its last step. With the parts in this position they arethen closed to ground the wire "leading to contact f which is engaged ycontact f grounded over the wire f. This pair of contacts 7" and f areon the line relay L which is energized by rea.-

son of the closing of the subscribers circuit.

7 The release of the switch is effected by disengaging the holdingpawlof the shaft S which is caused by the energizing of the rebatterylead X to wire contacts t, t on .relay V, wire 25, to .wi'per s. Therelease wire t leads fromthe last contact 2!" of the bottom row ofcontacts to the normally closed springs t, t? on relay U,the

indicated by S, carries i the subscribers circuit after the alarm im-.

pulses have been transmitted. This circuit may be traced from t, relayT, wire t,

0 lastmentioned v Spring g fi d by the wire t to'the constep by stepmovement of the rotary magnets tact t" on the line relay L, whichlast'menscrlbers circuitand that it, is the movement of the armature ofthisrelay that causes the R and the shaft S and consequently the springf alternatelyenga es the contacts f an ti", the latter furnis ing theground over which the release of the 'switch shaft S is effected, butthat this. release does not ocour while the impulses are beingtransmitted regularly at a predetermined rate because of' the sloweraction of the relays U and V, the

residual magnetism of which holds said re lease circuit open'momentarily while the switch wipers are stepping from one contact 0 vto another.

Now in order that the connector switch may be released automatically inthe event a subscriber accidentally 'picks' up this cir- -cuit and,further, to requ re said switch to b6 operated by elevenor moreimpulses, the first nine contacts of the lower row are joined together,as indicated; by w and are also connected to .the first contact yof themiddle row. It-will be noted that the Wipers s and s are set on a shaftS-in such position that they do not engage the first contact of theirrespective rows-of terminals upon the I first step ormovement of theshaft S, .but

that middle wiper s does engage the first contact 3/ in readiness totransmit the release impulsein the event 'the wipers are 'not furtheradvanced. Upon the second movement of the wi ei-s a a, a the lastmentioned wiper engages the first contact of its row and asal of thesecontacts with the exception of the last one are cornnectedwith groundover the wire W the releasewill be effected if the switchis allowed tostop in any one of the first ten positions since ten is the greatestnumber of impulses that can.

be despatched 'by the subscribers sendligs impulse mechanism A. Theresult descri might .be accomplished without offsetting the wipers s, swith relation to the middle wipers a, but this would require making theswitches with eleven or more contacts in each row ind it will,therefore, be seen that the scheme that I have suggested of ofl'settingthe wipers is that all of the parts can be made to conform to switchmechanism in use at the present time. In other words,

- I am enabledto carry out my invention by arm S and-S a circuit isestablished from S, wire .f, to the ma be transmitted after thecessation of im- Wiper S reaches contact t there is an ill-- terval oftime when the subscribers circuit is closed prior to the switching ofthe control to the box number wheel D. The circuit is at onceestablished from battery, wire f, contacts f, f, wire f, switch arm S,wire 7, relay M to battery lead X. This energizes relay M breakingcontacts m, m, thereby deenergizing relay V, closing contactst i whichthereby completes the circuit to the release magnet T with'the exception of holding it open at contacts t and f of relay L. After thecompletion of the fire alarm call, the subscribers'line is opened,deenergizing relay L, .closing its contact, thereby energizing releasemagnet T restoring the switch to normal position.

7 At the time the switch 'is first established in reaching the adjustedposition of switch ground,'wire f, contactsf, f, wire arm at Zcontrolhngthe recording apparatus at fire headquarters. The operation ofthe release magnet T is prevented while the switch arm S? is beingstepped around by the opening of the circuit of said magnetat thecontacts t, t by energization of the relay- V, over a circuit; leadingfrom battery lead X, and connected to the wire r, the result being thatrotary gnet R and relay V are connected in multiple and, therefore,relay V is continually energized while rotary magnet is receivingimpulses, due to the fact that "the relay V is slow acting. The circuitof the release magnet' T must be opened after the wiper S has reachedthe contact t, so that impulses from ground over the wire t may pulsesthrough line 'relay L, which is accomplished by providing a relay M in acircuit connected on one side to battery lead X and on the other to wireI", leadingfrom the last contact on the bank traversed by switch arm S;When said switch stops the last position the relay M is energized,thereby breakinga pair of contacts m" and m interposed in wire rof thecircuits of relay V and rotary magnet R.

This results in restoring the circuit of the magnetT at'the contacts t,t in readiness fora release impulse when the, fire alarm impulses haveceased, and interrupts passage of current to the rotary magnet R;

From the foregoing it willbe seenthat upon 1 the transmission of'theeleven impulses 1n At the same time the back release circuit isestablished so that the connector repeater its circuit opened by theopening of contacts f and 1) wire at, contact If, switch arm S wire tcontacts t wire release magnet T, wire t-to battery lead X. Thisenergizes release magnet T, restoring the switch to its normal position.

I claim as my invention:

1. The combination with an automatic telephone exchange systemcomprising a subscribers circuit provided with a manual impulsetransmitter adapted to despatch impulses limited to a given maximumnumber,. and automatic switches controlled by said impulses, of an alarmimpulse transmitting mechanism associated with said subscribers circuitadapted to transmit current impulses of a number greater than themaximum number which may bedespatched by the manual transmitter, aconnector switch comprising cooperating wipers and contacts and meansfor driving the wipers in accordance with the current impulses when ac}tuated by a number of impulses less than the total transmitted by thealarm transmitter, and an alarm trunk leading. from the contacts of theswitch upon which the wipers rest after being advanced.

2. In an automatic alarm apparatus for an automatic telephone exchangesystem, the combination with subscribers lines equipped with manualimpulse transmitters capable of despatching impulses of a given maximumnumber. and automatic switches for connecting said lines and an alarmimpulse transmitting mechanism capable of despatching impulses 'of agreater total number than said manual mechanism, of a connector switchadapted to be actuated by I the combination I equlpped with manuallysaid impulses, comprising cooperating wipers and contacts, means foradvancing the wipers, and devlces for restoring them to normaluponcessation of the transmission of current impulses less in numberthan the total number of those despatched by the alarm transmitter andan alarm trunk circuit leading from the terminals of said switch uponwhich the wipers restat the limit of their movement.

,3.'In an automatic alarm apparatus for an automatic telephone exchangesystem, with subscribers lines 7 operated impulse transmitters capableof transmitting a maximum number often current impulses and wipers inany of the first ten positions and an alarm circuit leading from thecontacts engaged by the wipers in their eleventh position of movementhaving alarm apparatus thereon.

4. In an automatic alarm apparatus for an automatic telephone exchangesystem, the combination with subscribers lines equipped with manuallyoperated impulse transmitters capable of transmitting 'a maximum numberof ten current impulses,

-an automatic alarm impulse transmitter adapted to despatch a greaternumber of such impulses, and an alarm circuit -provided with alarmapparatus, of an auto matic switch mechanism having cooperating wipersand contacts and rotary driving de-' vices actuating the wipers one stepfor each impulse transmitted by either of the transmitting mechanismsand also provided with release devices for restoring the wipers to theirnormal position, said release devices being adapted to be automaticallyoperated upon the cessation of impulses which leave the wipers in anyone of their first ten steps, but which are capable of operation in theusual manner by line control upon the eleventh or subsequent steps, and.an alarm 10 circuit leading from terminals with which the wipersengagewhen allowed to rest after the tenth step. 5. A' connector switchfor use in transmittmg alarm impulses over the "lines of automatictelephone systems comprising a bank of contacts arranged in a pluralityof rows one of which comprises. ten contacts, a set of line and releasewipers, means for advancing the engagement with said contacts, saidcontacts and wipers being so positioned relatively to'ea ch other whenthe wipers are in the normal position that one step is reimpulses of thealarm impulse transmitting mechanism and incapable of being set by themanual impuls transmitter atom-said. 130

latter step-by-step into 7. The combination with an automatic telephoneexchange system, including a, subscribers circuit provided with a manualimpulse transmitter for despatching impulses, of an alarm impulsetransmitting mechanism associated with said subscribers c1reu1t adaptedto transmit current 1mpulses, and a connector repeater switch includingcooperating wipers and contacts being capable of operation to apredetermined position by the impulses despatched by the alarm impulsetransmitting mechanism and incapable of: operation to such predeterminedposition by the impulse from the manual impulse transmitter aforesaid.

8. The combination with anautomatic telephone exchange system includinga subseribers circuit provided with a manual impulse transmitter fordespatching impulses, of an alarm impulse transmitting mechanismassociated wlth said subserlbers circuit and adapted to transmit currentimpulses, and a connector repeater switch ineluding wipers and contactscapable of beset for a predetermined eo-,

ing relatively operation by the impulse despatched by the alarm impulsetransmitting mechanism and incapable of being so set by the impulse fromthe subscribers manual impulse transmitter.

9. In an automatic telephone exchange system including a subseriberscircuit projvided with a manual impulse transmitter 10. In an automatictelephone exchange system including a subscribers circuit provided witha 'manualimpulse transmitter capable of transmitting a maximumnumber ofimpulses, of 'a connector repeater switch incapable of being set by themaximum or less number ,of impulses transmitted by the manual impulsetransmitter, and means associated with the subscribers circuit fortransmitting impulses in excess of the maximum number transmitted by themanual impulse transmitter for setting the switch aforesaid.

1 JOHN ERICKS ON.

Witnesses:

HYMAN L. Wmss, DAVID G. DEE.

